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Abstract Assessing volcanic hazards in locations exposed to multiple central volcanoes requires to consider multiple potential eruption sources and their respective characteristics. While this is common practice in ashfall hazard assessment, this is generally not considered for topography-controlled volcanic flow processes. Yet, in volcanic areas with closely spaced volcanic systems, eruptions fed from several contrasted volcanic systems might threaten one given area. Considering the case of the Nyiragongo and Nyamulagira volcanoes in the Virunga Volcanic Province (D.R.Congo), we present a method to produce a combined lava flow inundation susceptibility map that integrates both volcanoes. The spatial distribution of the probability of vent opening for the next eruption is separately constrained for both volcanoes based on the mapping of historical and pre-historical eruptive vents and fissures. The Q-LavHa lava flow probability model is then calibrated separately for each volcano, considering several historical lava flows of Nyamulagira (2004, 2006, 2010) and Nyiragongo (2002). The maps for the two volcanoes are thereafter integrated based on a weighted sum of both individual lava flow inundation probability maps, assuming historically-based relative eruption frequency of the two volcanoes. The accuracy of this probabilistic susceptibility map for the most active volcanic region in Africa was unfortunately validated by the May 2021 lava flow produced by Nyiragongo. This map was discussed and validated in 2019 with local scientists, as well as representatives of disaster management and urban planning institutions, but was not included in the regional contingency plan ahead of the 2021 eruption crisis. Updating the volcanic crisis and evacuation management plans with this lava flow probability map could contribute to reinforce risk awareness among the population and inform the future development of the city of Goma.

Understanding rodent-ectoparasite interactions and the factors driving them is important in understanding the epidemiology of diseases involving an arthropod vector. Fleas are the primary vector for Yersinia pestis, the bacteria that causes plague and monitoring of flea population is essential for planning the potential mitigation measures to prevent the disease outbreak. In this study, we investigated flea abundance, community structure and the potential factors driving flea infestation in areas with frequent (persistent) and non-frequent plague (non-persistent) outbreaks. We collected fleas from captured rodents in two villages with both forest and farm habitats. We found 352 fleas belonging to 5 species with Dinopsyllus lypusus the most abundant overall (57.10%) and Ctenophthalmus spp. the lowest (1.70%). There were no significant differences of flea abundance between study localities, habitats and seasons (p > 0.05) but, flea infestation was significantly positively associated with the persistent locality and with the short rain season (p

Abstract The multimammate mice (Mastomys natalensis) is the most-studied rodent species in sub-Saharan Africa, where it is an important pest species in agriculture and carrier of zoonotic diseases (e.g. Lassa virus). Here, we provide a unique dataset that consists of twenty-nine years of continuous monthly capture-mark-recapture entries on one 3 ha mosaic field (MOSA) in Morogoro, Tanzania. It is one of the most accurate and long-running capture-recapture time series on a small mammal species worldwide and unique to Africa. The database can be used by ecologists to test hypotheses on the population dynamics of small mammals (e.g. to test the effect of climate change), or to validate new algorithms on real long-term field data (e.g. new survival analyses techniques). It is also useful for both scientists and decision-makers who want to optimize rodent control strategies and predict outbreaks of multimammate mice.

Trichuriosis is a disease in mammals caused by the whipworms of the genus Trichuris. These worms are known for the high disease burden they cause in humans and domestic animals, especially in sub-Saharan Africa. In this study, we investigated the prevalence and seasonal variations of Trichuris worms in multimammate rats (Mastomys natalensis). The study was conducted between January and November 2021 in Tanzania, in two regions (Morogoro and Iringa) that differ in their eco-climatic conditions. Removal trapping was conducted using Sherman® live traps during the rainy and dry seasons. The gastrointestinal tracts of captured rodents were screened for the presence of Trichuris worms, which were identified using morphological keys. A total of 200 M. natalensis rats were collected from each of the regions, with 100 animals in each season. For Morogoro, the overall prevalence of Trichuris worms in M. natalensis was 36% (n = 72), of which 42% (n = 42) and 30% (n = 30) were for the rainy and dry seasons, respectively. For Iringa, the overall prevalence was 65% (n = 130), of which there were 80% (n = 80) and 50% (n = 50) for the rainy and dry seasons, respectively. Trichuris worm infections were significantly higher during the rainy season in Iringa than in Morogoro; however, no significant difference in infections between males and females was noted in either region or season. Other helminths detected were Strongyloides spp., Capillaria spp., Hymenolepis spp. and eggs of a helminth that has yet to be confirmed, possibly an Anoplocephalid species. Since M. natalensis is the most important pest species in sub-Saharan Africa, and is a carrier of several zoonotic helminths, there is a need for improved surveillance of helminths infections in the studied regions, in order to establish strategic control programs to reduce their adverse impacts on health.

Abstract Background Rodents form the largest order among mammals in terms of species diversity, and home range is the area where an individual normally moves during its normal daily activities. Information about rodent home ranges is paramount in the development of effective conservation and management strategies. This is because rodent home range varies within species and different habitats. In Uganda, tropical high altitude forests such as the Mabira Central Forest Reserve are experiencing continuous disturbance. However, information on rodent home range is lacking. Therefore, a two year Capture-Mark-Release (CMR) of rodents was conducted in the intact forest habitat: Wakisi, regenerating forest habitat: Namananga, and the depleted forest habitat: Namawanyi of Mabira Central Forest Reserve in order to determine the dominant rodent species, their home ranges, and factors affecting these home ranges. The home ranges were determined by calculating a minimum convex polygon with an added boundary strip of 5 m. Results Overall, the most dominant rodent species were: Lophuromys stanleyi, Hylomyscus stella, Praomys jacksoni Mastomys natalensis, Lophuromys ansorgei, and Lemniscomys striatus. H. stella dominated the intact forest habitat, while L. stanleyi was the most dominant both in the regenerating and the depleted forest habitats. L. stanleyi had a larger home range in the depleted forest, and the regenerating forest habitats, respectively. In the regenerating forest habitat, M. natalensis had a larger home range size, followed by L. stanleyi, and L. striatus. While in the intact forest habitat, H. stella had the largest home range followed by P. jacksoni. H. stella, L. striatus, L. stanleyi, M. natalensis, and P. jacksoni were most dominant during the wet season while L. ansorgei was relatively more dominant during the dry season. L. ansorgei, and P. jacksoni had a larger home range in the dry season, and a lower home range in the wet season. H. stella, L. stanleyi, M. natalansis and L.striatus had larger home ranges in the wet season, and lower home ranges in the dry season. The home ranges of the dominant rodent species varied across the three habitats in Mabira central forest reserve ( $${F}_{(2, 15)}= 6.41$$ F ( 2 , 15 ) = 6.41 , $$p = 0.000$$ p = 0.000 ). Conclusion The significant variation in home ranges of the dominant rodent species in Mabira Central Forest Reserve depending on the type of habitat presupposes that the rodent management strategies in disturbed forest reserves should focus on the type of habitat.

Viral Haemorrhagic Fever Outbreak presents a significant public health threat, requiring a timely, robust, and well-coordinated response. This paper aims to describe the roles of the Tanzania Field Epidemiology and Laboratory Training Program (TFELTP) graduates and residents in responding to Tanzania's first Marburg Viral Disease (MVD) outbreak. We performed a secondary data analysis using a range of documents, such as rosters of deployed responders and the TFELTP graduate and resident database, to count and describe them. Additionally, we conducted an exploratory textual analysis of field deployment reports and outbreak situational reports to delineate the roles played by the residents and graduates within each response pillar. A total of 70 TFELTP graduates and residents from different regions were involved in supporting the response efforts. TFELTP graduates and residents actively participated in several interventions, including contact tracing and follow up, sensitising clinicians on surveillance tools such as standard case definitions, alert management, supporting the National and Kagera Regional Public Health Emergency Operations Centres, active case search, risk communication, and community engagement, coordination of logistics, passenger screening at points of entry, and conducting Infection Prevention and Control (IPC) assessments and orientations in 144 Health Facilities. The successes achieved and lessons learned from the MVD response lay a foundation for sustained investment in skilled workforce development. FELTP Training is a key strategy for enhancing global health security and strengthening outbreak response capabilities in Tanzania and beyond.

Adolescent girls' capacity to lead healthy lives and perform well in school has been hampered by their lack of awareness about menstruation and the requirements for its hygienic management. Lack of enabling infrastructure, improper menstrual supplies, and limited socioeconomic support for good menstrual health and cleanliness are characteristics of schools in Africa South of the Sahara. We evaluated school-age girls' knowledge of menstrual hygiene and identified bottlenecks that could affect policy and programming for menstrual health and hygiene. A school-based cross-sectional study involved 8,012 adolescent school girls in the age group of 11-18 years (mean age = 14.9 years). The study evaluated students' knowledge of menstrual health and hygiene (MHH) from the viewpoints of schools and communities using a combination of qualitative and quantitative approaches. Data was collected using self-administered surveys, focus group discussions, in-depth interviews, and site observations. Girls' older age (AOR = 1.62, P 0.001), having a female guardian (AOR = 1.39: P = 001), and having a parent in a formal job (AOR = 1.03: P 0.023) were positively associated with Menstrual health and Hygiene Knowledge. MHH knowledge levels varied significantly between girls attending government (53.3) and non-government schools (50.5%, P = 0.0001), although they were comparable for girls attending rural and urban schools. Only 21% of the study's schools had at least one instructor who had received training in MHH instruction for students. We have established that the majority of adolescent girls in schools have inadequate knowledge on menstrual health and hygiene, and that school teachers lack the skills to prepare and support young adolescents as they transition into puberty. Concerted actions aimed at building supportive policy are paramount, for school-aged teenagers to learn about and reap the long-term advantages of good menstrual health practices.

إنّ مصطلح ”علم الدلالة” هو أحد أبرز الموضوعات المطروحة على جميع مستويات اللغة، بما يتضمّن من إمكانيّة إعطاء الكلمات معنىً واحداً أو أكثر. ويعتبر هذا النهج من أكثر الموضوعات فاعلية للتحقيق في النصوص الدينيّة ومنها الصحيفة السجاديّة التي تتمتّع بالبلاغة والقدرة العالية على استحداث المفاهيم والأفكار. فالملاحظة الأولى التي يمكن الإلتفات لها من خلال نظرة سريعة على أدعية الصحيفة السجاديّة هي الإختيار المناسب والترتيب الدقيق للكلمات على مستوى المفردات. ومن بين المفردات المتعدّدة في الصحيفة السجاديّة، فقد لعبت كلمتي القوّة والقدرة دوراً هاماً في إستقراء المعاني التي يريدها الإمام السجّاد () كالمفاهيم السياسيّة والعقائدية والاجتماعية والدينية وغيرها. لقد اعتمد هذا البحث الطريقة الوصفيّة التحليليّة، وذلك بعد دراسة لغويّة ودلاليّة لهاتين الكلمتين في مظاهرهما الدلالية المختلفة في الصحيفة السجاديّة. لذلك استعملت هاتان الكلمتان في الصحيفة السجادية لمعاني ومفاهيم مختلفة مثل الإرادة وقوّة القلب والقوة الجسدية والروحية، كما شُخِصَت كلمة "القوّة" بأنّها تختصّ بالشعور والعاقل أكثر من "القدرة

Concentrations of heavy metals namely Cr, Fe, Cu, Zn, As, Cd and Pb in African Sharptooth Catfish (clarias gariepinus) and sediment from river Mtakuja Tanzania were analyzed using the Energy Dispersive X-ray Fluorescence spectrometry technique. 32 samples from fish and sediment were investigated. The results show that the concentration of heavy metals was higher in upstream areas than in the downstream area. The concentration of Fe of 428.5 mg/kg in catfish from the upstream area was about 2 times 243.8 mg/kg obtained from the same fish in the downstream area. Similar cases observed for sediments with Fe concentration of 127626.9 mg/kg from upstream that was about 6 times higher than that of 21460.3 mg/kg from downstream area. The concentration of 44.8 mg/kg for Cu in the upstream area sediment was also about 2 times higher than 23.2 mg/kg in the downstream area sediment, while for as the concentration of 13.2 mg/kg was measured in the upstream, which is which is more than 5 times 2.5 mg/kg measured in downstream. The concentration of Cr in the catfish was 17.6 mg/kg which is higher than the permissible limit values of 0.8 mg/kg set by the European Commission (EC), 0.2 mg/kg set by the Food and Agricultural Organization (FAO) and 0.15 mg/kg the World Health Organization (WHO) limit. Moreover, the concentration of Cd was 3.0 mg/kg, which is above the permissible level of 0.2 mg/kg recommended by the EC and WHO. A positive correlation exists between the Cu, Pb, Fe and Cd concentration found in sediments and fish samples. The results show that the river Mtakuja is polluted by mining waste, domestic and agrochemical activities. This suggest that, there is a need for regular monitoring of heavy metal in river Mtakuja in order to monitor and protect aquatic organisms and health of benefactors of this river.

Background: Leptospirosis is one of the most commonly neglected zoonoses in developing nations including Tanzania. This study aims to find out the seroprevalence of leptospirosis in rodents, shrews, and domestic animals in different regions in Unguja Island, Tanzania. Methods: A cross-sectional study was carried out from January to April 2022. The blood samples were collected from rodents and shrews (n=248), cattle (n=247), goats (n=130), sheep (n=32), and dogs (n=80). The blood samples were allowed to clot in a slanted position and serum samples were harvested. A microscopic agglutination test (MAT) was performed on the sera to check for leptospiral antibodies using five Leptospira serovars as antigens (Sokoine, Lora, Pomona, Grippotyphosa and Hebdomadis). Results: The overall seropositivity of leptospiral antibodies was 9.68% in rodents and shrews, 14.57% in cattle, 10.01% in goats, 31.25% in sheep, and 26.25% in dogs. The seropositivity of Leptospira varied significantly with animal species (OR=1.9, 95 % CI:1.1-3.3, p=0.03). The most frequently detected serovar was Sokoine (27.89%), followed by Pomona (19.47%), Lora (18.26%), Grippotyphosa (17.98%), and Hebdomadis (8.16%), respectively. Conclusion: Our study suggests that further research should be conducted to find out factors of high seropositivity of leptospiral in Unguja. Vaccination of domestic animals with vaccines against local Leptospira strains should be encouraged, and rodent control and public awareness should be emphasized.

This article is part of the Research Topic ‘Health Systems Recovery in the Context of COVID-19 and Protracted Conflict’.The COVID-19 pandemic has exposed the vulnerabilities and limitations of many health systems and underscored the need for strengthening health system resilience to make and sustain progress toward Universal Health Coverage (UHC), global health security and healthier populations in tandem. In response to the COVID-19 pandemic, Commonwealth countries have been practicing a combination of innovative integrated approaches and actions to build health systems resilience. This includes utilizing digital tools, improvements in all-hazard emergency risk management, developing multisectoral partnerships, strengthening surveillance and community engagement. These interventions have been instrumental in strengthening national COVID-19 responses and can contribute to the evidence-base for increasing country investment into health systems resilience, particularly as we look toward COVID-19 recovery. This paper gives perspectives of five Commonwealth countries and their overall responses to the pandemic, highlighting practical firsthand experiences in the field. The countries included in this paper are Guyana, Malawi, Rwanda, Sri Lanka, and Tanzania. Given the diversity within the Commonwealth both in terms of geographical location and state of development, this publication can serve as a useful reference for countries as they prepare their health systems to better absorb the shocks that may emerge in future emergencies.

Abstract Background Tanzania ranks as the fourth country in the world with respect to the number of sickle cell disease (SCD) births; it is also endemic to the human immunodeficiency virus (HIV) and the hepatitis B virus (HBV). This study was done to determine the prevalence of HIV and HBV infections among SCD patients in Dar es Salaam, Tanzania. Methods A multicenter hospital-based descriptive cross sectional study was carried out among participants aged ≥ 16 years with a proven diagnosis of SCD. Socio-demographic and clinical data were recorded. Blood samples were drawn for HIV and HBV diagnosis. All categorical variables were summarized into frequencies. Results There were 185/325 (56.9 %) females. The mean age (SD) was 23.0 ± 7.5 years. The prevalence of HIV was 1.8 %; the prevalence of HBV was 1.2 %. Conclusions The prevalence of both HIV and HBV in SCD patients is no greater than in the general population of Dar es Salaam or Tanzania. For associations, a large study would be needed. From a detailed blood transfusion history of SCD patients we found no evidence that HIV or HBV infection was transmitted through blood transfusion.

Climate change will put millions more people in Africa at risk of food and nutrition insecurity by 2050. Integrated assessments of food systems tend to be limited by either heavy reliance on models or a lack of information on food and nutrition security. Accordingly, we developed a novel integrated assessment framework that combines models with in-country knowledge and expert academic judgement to explore climate-smart and nutrition-secure food system futures: the integrated Future Estimator for Emissions and Diets (iFEED). Here, we describe iFEED and present its application in Malawi, South Africa, Tanzania and Zambia. The iFEED process begins with a participatory scenario workshop. In-country stakeholders identify two key drivers of food system change, and from these, four possible scenarios are defined. These scenarios provide the underlying narratives of change to the food system. Integrated modeling of climate change, food production and greenhouse gas emissions is then used to explore nutrition security and climate-smart agriculture outcomes for each scenario. Model results are summarized using calibrated statements—quantitative statements of model outcomes and our confidence in them. These include statements about the way in which different trade futures interact with climate change and domestic production in determining nutrition security at the national level. To understand what the model results mean for food systems, the calibrated statements are expanded upon using implication statements. The implications rely on input from a wide range of academic experts—including agro-ecologists and social scientists. A series of workshops are used to incorporate in-country expertise, identifying any gaps in knowledge and summarizing information for country-level recommendations. iFEED stakeholder champions help throughout by providing in-country expertise and disseminating knowledge to policy makers. iFEED has numerous novel aspects that can be used and developed in future work. It provides information to support evidence-based decisions for a climate-smart and nutrition-secure future. In particular, iFEED: (i) employs novel and inclusive reporting of model results and associated in-country food system activities, with comprehensive reporting of uncertainty; (ii) includes climate change mitigation alongside adaptation measures; and (iii) quantifies future population-level nutrition security, as opposed to simply assessing future production and food security implications.

Abstract Praomys delectorum occurs abundantly in both disturbed and intact forests in the Ukaguru Mountains within the Eastern Arc Mountains (EAM), Morogoro, Tanzania. While previous studies have reported that anthropogenic disturbances such as grazing, wood cutting, and harvesting have a positive effect on the population density of P. delectorum, the impact of habitat disturbance on its demographic traits is still unknown. We performed a capture–mark–recapture study in both disturbed and intact forests from June 2018 to February 2020 in order to investigate the effects of habitat disturbance on abundance and two demographic traits: survival and maturation of P. delectorum in the Ukaguru Mountains. We found no variation in abundance or maturation between intact and disturbed forests, but habitat type did affect survival. However, this effect was sex‐dependent since female survival was higher in disturbed forests, while male survival remained similar across the two forest types potentially due to differences in predation pressure or food availability between the two habitats. Continuous demographic monitoring of P. delectorum in EAM is necessary given that the increasing human population surrounding the landscape is leading to higher deforestation rates and expansion of the pine plantation in the forest reserve.

Evolutionary information on the greater cane rat (Thryonomys swinderianus) in the Eastern and Southern African regions is scarce, making population management and conservation of the species challenging. We studied T. swinderianus populations from two spatially isolated Eastern Arc Mountains in Tanzania to link molecular and geometric–morphological evidence to characterize these populations’ diversity. Fecal samples (n = 50) and skulls (n = 99) of T. swinderianus were collected from Udzungwa (north and south) and Uluguru mountains (urban and rural sites) and analyzed using molecular and geomorphometry techniques. Molecular analysis grouped the population into three distinct clades based on the location where the samples were collected, while the morphometric method was not able to distinctively separate the populations. Both methods revealed that the population obeyed the isolation by distance model with higher genetic distance between the Udzungwa and Uluguru populations and lower distance between Uluguru urban and rural populations. Both Mahalanobis and Procrustes distances in skull landmarks between the Udzungwa and Uluguru populations were significantly higher across the dorsal, ventral, and lateral views of the skulls, suggesting strongly that molecular and morphometric methods applied together can be useful in characterizing the population traits of the least known species. Our study suggests genetic and morphometric methods could complement each other in understanding the evolutionary biology and within-species diversity of vertebrate species that do not exhibit strong intra-species differentiation.

Tsushima leopard cats (TLC; Prionailurus bengalensis euptilurus) only inhabit Tsushima Island, Nagasaki, Japan and are critically endangered and threatened by infectious diseases. The feline foamy virus (FFV) is widely endemic in domestic cats. Therefore, its transmission from domestic cats to TLCs may threaten the TLC population. Thus, this study aimed to assess the possibility that domestic cats could transmit FFV to TLCs. Eighty-nine TLC samples were screened, and FFV was identified in seven (7.86%). To assess the FFV infection status of domestic cats, 199 domestic cats were screened; 14.07% were infected. The phylogenetic analysis revealed that the FFV partial sequence from domestic cats and TLC sequences clustered in one clade, suggesting that the two populations share the same strain. The statistical data minimally supported the association between increased infection rate and sex (p = 0.28), indicating that FFV transmission is not sex dependent. In domestic cats, a significant difference was observed in FFV detection in feline immunodeficiency virus (p = 0.002) and gammaherpesvirus1 infection statuses (p = 0.0001) but not in feline leukemia virus infection status (p = 0.21). Monitoring FFV infection in domestic cats and TLC populations is highly recommended as part of TLC surveillance and management strategies.

Climate change causes organisms, including species that act as parasite reservoirs and vectors, to shift their distribution to higher altitudes, affecting wildlife infestation patterns. We studied how ectoparasite distributions varied with altitude using two rodent species, Montemys delectorum and Rhabdomys dilectus, at different elevations (1500–3500 m). The ectoparasites infesting the two rodent species were influenced by the host sex, species, and temperature. We expected host density to predict parasite infestation patterns, because hosts in higher densities should have more parasites due to increased contact between individuals. However, temperature, not host density, affected ectoparasite distribution. Since temperatures decrease with elevation, parasite prevalences and abundances were lower at higher elevations, highlighting that the cold conditions at higher elevations limit reproduction and development—this shows that higher elevation zones are ideal for conservation. The rodents and ectoparasite species described in this study have been reported as vectors of diseases of medical and veterinary importance, necessitating precautions. Moreover, Mount Meru is a refuge for a number of endemic and threatened species on the IUCN Red List. Thus, the parasitic infection can also be an additional risk to these critical species as well as biodiversity in general. Therefore, our study lays the groundwork for future wildlife disease surveillance and biodiversity conservation management actions. The study found a previously uncharacterized mite species in the Mesostigmata group that was previously known to be a parasite of honeybees. Further investigations may shed light into the role of this mite species on Mount Meru.

This paper presents effects of lithium (Li) and magnesium (Mg) dopants on the dielectric properties of ZnO ceramics with emphasis on ferroelectricity prospects of co-doped samples with Zn0.7Li0.28Mg0.02O compositions. Ceramics with average relative density ∼97% were produced by solid-state-reaction of mechanically activated powder precursors using 1000 °C for 2 h sintering conditions. Room temperature A.C. conductivity σa.c(ω) and temperature-frequency (T-ω) dependence of dielectric permittivity (ε′) and loss (ε″) of the samples are measured within temperature range from −100 to 150 °C in air and in a vacuum cryostat with liquid nitrogen coolant. Undoped ZnO σa.c(ω) data exhibits a nearly insensitive dependence to the ω while that of doped samples show significant ω dependence and higher σa.c(ω) values than undoped ZnO ceramics. Anomalous ε′ and ε″ peaks were observed in Zn0.7Li0.28Mg0.02O specimens around TC of −25 °C during cooling and −10 °C during heating measurements in air. However, dielectric properties of the same Zn0.7Li0.28Mg0.02O ceramics obtained in vacuum cryostat and from undoped ZnO ceramics in air and in vacuum cryostat did not reveal any ε′ and ε″ transition peaks at low temperature.

This paper presents effects of powder mechanical activation and controlled sintering on the densification properties of ZnO ceramics with Lithium (Li) and Magnesium (Mg) dopants. Dense bodies of Zn1-xLixO and Zn0.7Li0.28Mg0.02O ceramics were prepared via solid-state-reaction of mechanically activated mixtures of ZnO, Li2CO3 and MgO reactant raw powders. The density, surface microstructure, porosity and phase purities of the ceramics were investigated with a Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) techniques. The study highlights mechanical activation processes such as milling, calcination and compaction steps that are needed to overcome complicated interactive reactions during conventional sintering of Zn1-xLixO and Zn0.7Li0.28Mg0.02O ceramics that have been reported to show ferroelectric behavior. The results show that, densely packed single phase Zn1-xLixO and Zn0.7Li0.28Mg0.02O ceramics with average relative density values above 96% and single phase hexagonal wurtzite crystalline structure were achieved at a sintering temperature of 1000 °C for 2 h in air.

Abstract Pest rodents remain key biotic constraints to cereal crops production in the East African region where they occur, especially in seasons of outbreaks. Despite that, Uganda has scant information on rodents as crop pests to guide effective management strategies. A capture–mark–recapture (CMR) technique was employed to study the ecology of small rodents, specifically to establish the species composition and community structure in a maize‐based agro ecosystem. Trapping of small rodents was conducted in permanent fallow land and cultivated fields, with each category replicated twice making four study grids. At each field, a 60 × 60 m grid was measured and marked with permanent trapping points spaced at 10 × 10 m, making a total of 49 trapping points/grids. Trapping was conducted monthly at 4‐week interval for three consecutive days for two and half years using Sherman live traps. Eleven identified small rodent species and one insectivorous small mammal were recorded with Mastomys natalensis being the most dominant species (over 60.7%). Other species were Mus triton (16.1%), Aethomys hendei (6.7%), Lemniscomys zebra (5.2%), Lophuromys sikapusi (4.8%), Arvicanthis niloticus (0.9%), Gerbilliscus kempi (0.1%), Graphiurus murinus (0.1%), Steatomys parvus (0.1%), Dasymys incomtus (0.1%), and Grammomys dolichurus (0.1%). Spatially, species richness differed significantly (p = 0.0001) between the studied field habitats with significantly higher richness in fallow land compared with cultivated fields. Temporally, total species richness and abundance showed a significant interaction effect over the months, years, and fields of trapping with significantly (p = 0.001) higher abundances during months of wet seasons and in the first and third year of trapping. In terms of community structure, higher species diversity associated more with fallow field habitats but also with certain rare species found only in cultivated fields. Synthesis and applications. Based on these findings, management strategies can be designed to target the key pest species and the most vulnerable habitats thus reducing the impact they can inflict on field crops.

Understanding species distribution across elevational gradients is crucial for developing conservation strategies for montane biotic systems. A survey of small mammals was conducted on Mount Meru at six elevations, ranging between 1500 m and 3650 m. A total of 803 small mammal individuals, including 2 shrew species and 13 rodent species, were documented. Of these, Crocidura newmarki and Lophuromys verhageni were endemic on Mount Meru. Species richness was highest at mid–elevations, which is in line with the global pattern for small mammals. Prior to our study, the most complete data on small mammals on Mount Meru was collected in 2009. Our study provides an opportunity to show how small mammal elevational distribution has changed, over the last decade. We found six species (Arvicanthis niloticus, Mastomys natalensis, Lemniscomys striatus, Dasymys incomtus, Cricetomys ansorgei, and Montemys delectorum), which were not documented in 2009, but did not find Otomys tropicalis. Interestingly, the community composition at higher elevations in 2021 resembles that at lower elevations in 2009, suggesting that small mammal species have moved their range upward over time. Climate change could be a factor associated with the distributional shift found.

Background and aim: African Greater Cane (ACG) rat populations are widely distributed across Africa but the ancestral origin of populations inhabiting different geographical regions is unknown. There is currently no information available on the genetic differentiation of these populations resulting from long-time geographical isolation, environmental and anthropogenic pressures they face in each region. This limits our ability to understand potential speciation processes in AGC and their implications for their conservation and of other small wild mammals exposed to similar ecological conditions in the savannah biomes in Africa. Methods: We analyzed mitochondrial genes targeting the D-loop region of AGC samples from two blocks of the Eastern Arc Mountains in Tanzania (eastern), three agro-ecological zones in Ghana (western) and four sites in South Africa (southern) to characterize the phylogeographical patterns of the species. Results: AGC populations from Tanzania revealed higher haplotype diversity than those from the two other régions. Analysis of variance (AMOVA) revealed higher genetic variations within than between populations in all geographic regions. Demographic history analysis revealed a negative and significant Tajima's D for a single southern African population as well as close relatedness with the Eastern Africa populations, suggesting a common ancestral origin. Conclusion: This is the first study to compare maternal lineages of AGC populations from eastern, western and southern Africa and provides a basis for future genetic studies of the species, its evolutionary ecology and the conservation of these populations across their range. Conservation implications: Evidence of recent population size expansion underpinned by high genetic diversity observed in the Uluguru urban (Tanzania) Guinea savannah (Ghana) and Kwazulu Natal (South Africa) populations suggest that the AGC populations are not currently threatened, consistent with the current IUCN status. Also, the distinct haplotypes observed in each region suggest that the populations can be managed as meta-populations, thus providing opportunities for potential local game-farming programs. [ABSTRACT FROM AUTHOR]

The diet and breeding patterns of Mastomys natalensis in semi-arid areas of Isimani division, Iringa region, Tanzania were investigated in maize fields and fallow land. The aim was to investigate the influence of diet on breeding patterns of M. natalensis. Removal trapping was used to capture rodents and analyse diet categories while Capture-mark-release trapping was used to investigate breeding patterns of female M. natalensis. Mastomys natalensis comprised 94% of the total capture, and the remaining 6% comprised of six other species. Statistical analysis of food preferences indicated that both vegetative materials and seeds were significantly higher in the overall diet of M. natalensis compared with other food materials. Significant differences in the proportions of vegetative materials and seeds were found between seasons (dry, wet), but not between habitats (fallow, maize). There was a clear seasonal pattern in the proportion of reproductively active females with peaks in April and troughs in October. The proportion of vegetative materials was highest during the wet season and correlated positively with reproductive activity, suggesting that vegetative materials contain certain compounds (e.g. 6-MBOA) that trigger reproductive activity in M. natalensis. The breeding activity of M. natalensis in semi-arid areas might, thus, be reduced by limiting access to fresh vegetative food (e.g. young sprouting grass).

Solar cooking is a sustainable way of cooking and heating that use direct energy from the sun. Despite the introduction of solar cookers in Tanzania, various challenges have hindered the adoption of this technology. This study aims to explore the level of awareness of solar cooking technology among community members, and the main barriers confronting its usage, while exploring factors that can strengthen its adoption in Tanzania. The study is informed by semi-structured questionnaires, in-depth interviews, and a review of relevant documents. The collected quantitative data were subjected to descriptive statistics, while qualitative data were brought under thematic analysis. The study found a good level of understanding and awareness of solar cooking technology among researched communities. Nevertheless, higher prices, poor designs, limited access, weather dynamics were found among factors discouraging successful adoption. Moreover, solar cooking adoption is incentivized by the relief from costs of using of conventional fuels such as fuelwood. The study concludes that solar cooking technology bears a great potential of environmentally friendliness, long term cost saving with zero operational costs, and protects the health of the users from some harmful cooking fuels. This study recommends more efforts to promote the domestic use of solar cooking through education to individuals in the communities and policy interventions to increase its adoption rate in Tanzania. • Awareness and preferences of community influenced adoption solar cookers. • The high costs of solar cookers have resulted in a lower adoption rate in Tanzania. • Some types of solar cookers are slower in cooking compared to fuelwood. • Integrating solar cooking into policymaking can increase adoption rate. [ABSTRACT FROM AUTHOR]

Many emerging infections are RNA virus spillovers from animal reservoirs. Reservoir identification is necessary for predicting the geographic extent of infection risk, but rarely are taxonomic levels below the animal species considered as reservoir, and only key circumstances in nature and methodology allow intrinsic virus-host associations to be distinguished from simple geographic (co-)isolation. We sampled and genetically characterized in detail a contact zone of two subtaxa of the rodent Mastomys natalensis in Tanzania. We find two distinct arenaviruses, Gairo and Morogoro virus, each spatially confined to a single M. natalensis subtaxon, only co-occurring at the contact zone's centre. Inter-subtaxon hybridization at this centre and a continuum of quality habitat for M. natalensis show that both viruses have the ecological opportunity to spread into the other substaxon's range, but do not, strongly suggesting host-intrinsic barriers. Such barriers could explain why human cases of another M. natalensis-borne arenavirus, Lassa virus, are limited to West Africa.

Rodent pests are especially problematic in terms of agriculture and public health since they can inflict considerable economic damage associated with their abundance, diversity, generalist feeding habits and high reproductive rates. To quantify rodent pest impacts and identify trends in rodent pest research impacting on small-holder agriculture in the Afro-Malagasy region we did a systematic review of research outputs from 1910 to 2015, by developing an a priori defined set of criteria to allow for replication of the review process. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We reviewed 162 publications, and while rodent pest research was spatially distributed across Africa (32 countries, including Madagascar), there was a disparity in number of studies per country with research biased towards four countries (Tanzania [25%], Nigeria [9%], Ethiopia [9%], Kenya [8%]) accounting for 51% of all rodent pest research in the Afro-Malagasy region. There was a disparity in the research themes addressed by Tanzanian publications compared to publications from the rest of the Afro-Malagasy region where research in Tanzania had a much more applied focus (50%) compared to a more basic research approach (92%) in the rest of the Afro-Malagasy region. We found that pest rodents have a significant negative effect on the Afro-Malagasy small-holder farming communities. Crop losses varied between cropping stages, storage and crops and the highest losses occurred during early cropping stages (46% median loss during seedling stage) and the mature stage (15% median loss). There was a scarcity of studies investigating the effectiveness of various management actions on rodent pest damage and population abundance. Our analysis highlights that there are inadequate empirical studies focused on developing sustainable control methods for rodent pests and rodent pests in the Africa-Malagasy context is generally ignored as a research topic.

[This corrects the article DOI: 10.1371/journal.pone.0174554.].

Felis catus gammaherpesvirus 1 (FcaGHV1) is a widely endemic infection of domestic cats. Current epidemiological data identify domestic cats as the sole natural host for FcaGHV1. The Tsushima leopard cat (TLC; Prionailurus bengalensis euptilurus) is a critically endangered species that lives only on Tsushima Island, Nagasaki, Japan. Nested PCR was used to test the blood or spleen of 89 TLCs for FcaGHV1 DNA; three (3.37%; 95% CI, 0.70–9.54) were positive. For TLC management purposes, we also screened domestic cats and the virus was detected in 13.02% (95% CI, 8.83–18.27) of 215 cats. Regarding phylogeny, the partial sequences of FcaGHV1 from domestic cats and TLCs formed one cluster, indicating that similar strains circulate in both populations. In domestic cats, we found no significant difference in FcaGHV1 detection in feline immunodeficiency virus-infected (p = 0.080) or feline leukemia virus-infected (p = 0.163) cats, but males were significantly more likely to be FcaGHV1 positive (odds ratio, 5.86; 95% CI, 2.27–15.14) than females. The higher frequency of FcaGHV1 detection in domestic cats than TLCs, and the location of the viral DNA sequences from both cats within the same genetic cluster suggests that virus transmission from domestic cats to TLCs is likely.

To determine the specificity of Morogoro virus for its reservoir host, we studied its host range and genetic diversity in Tanzania. We found that 2 rodent species other than Mastomys natalensis mice carry arenaviruses. Analysis of 340 nt of the viral RNA polymerase gene showed sympatric occurrence of 3 distinct arenaviruses.

The pattern of plague endemicity in Tanzania is characterized by continuous re-appearance of the disease in some locations, while in other neighbouring villages the disease has never or seldom been observed. To understand the reasons for this pattern, we studied small mammals and fleas species composition, diversity and relative abundances in two plague-endemic and two plague-free locations. We asked (a) whether fleas more abundant in plague-endemic locations differ in their characteristic abundance and the degree of their host specificity from fleas most abundant in plague-free locations and (b) whether hosts more abundant in plague-endemic locations differ in the diversity of their flea assemblages from hosts most abundant in plague-free locations. We characterized (a) host species by species richness and degree of taxonomic relatedness of its flea assemblages and (b) each flea species by its mean abundance and size, and degree of taxonomic relatedness of its host spectrum and compared their relative abundances between locations. No significant difference between plague-endemic and plague-free locations in either host density or any variable related to flea abundance or diversity was found. However, there was marginally significant effect of taxonomic distinctness of a flea assemblage harboured by a host on its probability to be more abundant in either plague-endemic or plague-free locations. Furthermore, hosts more abundant in plague-endemic locations tended to harbour closely-related fleas. Finally, while opportunistic and specialist fleas were equally distributed in both sets of locations, fleas exploiting distantly-related hosts were found mainly in plague-free locations during the rainy season. We suggest that the observed patterns might arise due to seasonal and spatial differences in local microclimatic conditions and landscape connectivity[Current Zoology 55(3):199–211, 2009].

A serosurvey involving 2,520 small mammals from Tanzania identified a hot spot of arenavirus circulation in Morogoro. Molecular screening detected a new arenavirus in Natal multimammate mice (Mastomys natalensis), Morogoro virus, related to Mopeia virus. Only a small percentage of mice carry Morogoro virus, although a large proportion shows specific antibodies.